Influenza-Associated Mortality in Georgia (2009–2011)

We analyzed data from NCDCPH Georgia where samples from outpatients with influenza-like illness (ILI) and inpatients with severe acute respiratory syndrome (SARI) are referred for testing on influenza virus using PCR analysis. During 2009-2010 and 2010-2011 influenza pandemics total number of the laboratory-confirmed influenza cases were 1286 with 33 deaths (all of them influenza type A) and 1203 (51.4% type A) with 44 deaths, respectively. At least one underlying medical condition was reported in 70.7% (for pandemic influenza strain) and 96% (for influenza type B) of deaths. Predominating preexisting condition was coronary heart disease. 1. Background Pandemic and seasonal influenza result in significant morbidity, increase in hospitalization rate and mortality. Even though influenza is usually mild and self-limited disease, among certain population groups, such as elderly people, very young children and patients with different underlying medical conditions (diabetes, cardiovascular and pulmonary comorbidities, and other chronic diseases), it may pose a serious risk with potential complications and death [1]. 2009 influenza pandemic involved the new strain of H1N1 virus. The pandemic had started in April 2009 in Mexico and spread worldwide. During 2010-2011 epidemic, according to the WHO report from countries of European Union, about 90% of subtyped influenza viruses from the hospitalized cases were pandemic strain of A (H1N1), 1%-A(H3N2) and 10%-influenza B viruses [2]. Unlike the seasonal influenza, during the 2009 pandemic the higher attack rates were documented among young adults compared to persons older than 60 [3, 4]. For both influenza seasons, neuraminidase inhibitors were recommended for treatment of pregnant women, children under two years, patients with severe, progressive disease, and for those having underlying chronic diseases. The objective of the study was to estimate mortality and underlying medical conditions among patients with influenza during 2009-2010 and 2010-2011 seasons in Georgia. The country started influenza surveillance from 2007 when Georgian National Center for Disease Control and Public Health (NCDCPH) became the National Influenza Center, a part of WHO Global Influenza Surveillance Network. 2. Methods We analyzed the data from NCDCPH where the samples from outpatients with influenza-like illness (ILI) and inpatients with severe acute respiratory syndrome (SARI) from sentinel sites throughout the country are referred to be tested for influenza virus. The following case definitions were used: ILI was defined as acute